Which one of the following sites of the Indus Valley Civilization had an ancient dockyard?

Lothal, located in the Bhal region of Gujarat near the Gulf of Khambhat, is the only site among the options that possessed an ancient dockyard [t1][t4]. Excavated by the Archaeological Survey of India, Lothal served as a vital maritime trade hub during the Mature Harappan period (c. 2400–1900 BCE) [t4][t7]. The dockyard is a sophisticated brick-walled structure, roughly trapezoidal in shape, designed to berth ships and facilitate trade with distant regions like Mesopotamia and Egypt [t6][t7]. It was strategically linked to an ancient course of the Sabarmati River, utilizing a sluice gate and spill channel to manage water levels and prevent siltation [t4][t6]. While other sites like Kalibangan are known for ploughed fields and Harappa for its urban layout, Lothal remains unique for its advanced maritime engineering and status as the world's earliest known artificial dock [t2][t4][t9].

Sources

1. [1] https://www.sciencedirect.com/science/article/abs/pii/S0305440324001146
2. [2] https://ncert.nic.in/textbook/pdf/lehs101.pdf